This application claims priority of a prior German application Serial No. 100 38 390.4-34 filed Aug. 7, 2000.
The present invention relates to a circuit substrate assembly comprising pairs of xe2x80x9cleft-handxe2x80x9d and xe2x80x9cright-handxe2x80x9d circuit substrates including electrical and/or electronic and/or electromechanical components positioned mirror-symmetrical to each other, it relating more particularly to circuit substrate assemblies as set forth in the preamble of claim 1 as known from DE 39 04 771 C1, DE 44 05 566 A1 and U.S. Pat. No. 5,612,777 in each case.
The objective forming the basis of the present invention is explained, by way of an example, with reference to FIGS. 3a to 6b. 
For controlling car door locks, use is made nowadays of electromechanical locking devices. Shown diagrammatically in FIGS. 3a or 3b is a plan view of the open pans 1, 1xe2x80x2 of a circuit substrate 2, 2xe2x80x2 for a left-hand and right-hand car door respectively.
The circuit substrates 2, 2xe2x80x2 are plastics substrate parts in which electric conductors are embedded which connect the electrical and/or electronic and/or electromechanical components to each other on the two circuit substrates 2, 2xe2x80x2.
In FIGS. 3a and 3b the components applied to the two circuit substrates 2 or 2xe2x80x2 are, for example, a first switch SW1 or SW1xe2x80x2, a second switch SW2 or SW2xe2x80x2, a first electric motor M1 or M1xe2x80x2, a second electric motor M2 or M2xe2x80x2 and a plug S or Sxe2x80x2. The electric motors are each symbolized by the contact terminals and the direction of rotation of the motor.
In series automobile production the situation calls for configuring the two circuit substrates 2, 2xe2x80x2 and their pans 1, 1xe2x80x2 as shown in FIGS. 3a and 3b for a left-hand and right-hand car door mirror-symmetrical to permit installing them on both sides of the motor vehicle positioned and oriented mirror-symmetrical to each other.
When imagining that a mirror plane P is oriented between the left-hand and right-hand variants of a circuit substrates 2, 2xe2x80x2 as shown in FIGS. 3a and 3b, then due to the symmetry requirements the positions and orientations of the components mounted on the left-hand circuit substrate 2 are mirror-symmetrical to the positions and orientations of the components mounted on the right-hand circuit substrate 2xe2x80x2.
It is particularly in series motor vehicle production that for reasons of simplifying material economy and cost savings in designing the variants there exists the marginal requirement that the number of component variants to be developed and held available is to be minimized. This means, for example, that no specific left-hand and specific right-hand variant is to be provided in each case for the components as shown in FIGS. 3a and 3b. By making use of only one variant of components the complexity requirements in installation and on the corresponding automated handling devices are also reduced in each case.
Instead, what is desired in series production is that the motors M1 and M2, the switches SW1 and SW2 and plug S as shown in FIG. 3a and all totally identical to the motors M1xe2x80x2 or M2xe2x80x2, the switches SW1xe2x80x2 and SW2xe2x80x2 and plug Sxe2x80x2 as shown in FIG. 3b. 
Accordingly, as regards their circuit-functional contact assignment and effectiveness, the components as shown in FIGS. 3a and 3b are not mirror-symmetrical to each other, i.e. the identical motors M1 in FIG. 3a and M1xe2x80x2 in FIG. 3b both rotate counter-clockwise, for example (and not opposite in rotation to each other) and the plug positions plug positions A-K of the plugs S or Sxe2x80x2 as shown in FIGS. 3a and 3b are likewise not mirror-symmetrical to each other, they instead corresponding to each other.
In other words, mirror-symmetry exists as regards the three-dimensional geometry of the installation situation for the left-hand and the right-hand variant of the circuit substrate, whereas asymmetry exists as regards the functionality of the circuit.
Due to the components being identical as shown in left-hand and right-hand configuration this also results in, in the case of car door locking devices, that for the mating the plugs and the wiring harnesses connected thereto a left-hand and right-hand variant does not need to be provided in each case, but instead only an identical variant to be installed on the left-hand and right-hand side of the vehicle as regards its symmetrical positioning and orientation in a three-dimensional geometry, but which is asymmetrical as regards its circuit functionality.
Since both circuit substrates as shown in FIGS. 3a and 3b are assigned exactly the same circuit diagram and the same contact pin assignment, as shown in FIG. 4 for example, two different layouts for the circuitry need to be designed for the circuitry in the left-hand and right-hand embodiment of the circuit substrates 2, 2xe2x80x2 for correctly contacting the left-hand and right-hand variant of the circuit substrates 2, 2xe2x80x2 in accordance with the circuit function.
Satisfying this requirement hitherto in actual practice was achieved by selecting a layout for the left-hand circuit substrates 2 different to that for the right-hand circuit substrates 2xe2x80x2, as evident from FIGS. 5a and 5b each showing a layout for a left-hand and a right-hand circuitry.
Referring now to FIGS. 6a and 6b there is illustrated, the same as shown in FIGS. 3a and 3b, how the circuitry as shown in FIGS. 5a and 5b is embedded in the circuit substrates 2, 2xe2x80x2 which is usually done by potting the circuit substrates in plastics.
When using e.g. a stamped matrix for the circuitry, then the layouts as shown in FIGS. 5a and 5b correspond to two different stamped matrixes, each of which is to be embedded in the left-hand and right-hand circuit substrates 2, 2xe2x80x2 respectively, this requiring, of course, two different stamping/bending dies for producing the stamped matrixes. In automated production this results in two production lanes totally separate from each other needing to be equipped including stamping/bending dies and automated handling devices each specifically adapted to the left-hand and right-hand stamped matrix. By making use of different stamping/bending dies for the left-hand and right-hand stamped matrix it is possible to configure on the two stamped matrixes, by suitably bending the free-standing stamped matrix sections, contact pins (not shown) permitting contacting the components to the two stamped matrixes as shown in FIGS. 6a and 6b such that the components are positioned mirror-symmetrical to each other on the left-hand and right-hand stamped matrix.
Similar problems are likewise involved when using circuit substrates with applied track arrays, e.g. in the form of of rigid circuit boards or flexible printed circuit films instead of stamped matrixes. Here too, two variants having different circuitry (layouts) needs to be provided for the left-hand and right-hand embodiment in the case of such circuit substrates provided with tracks, meaning that, e.g. two different kinds of exposure masks need to be employed in photolithographic circuit board production.
In any case, the problem remains of having to handle two different variants of the circuitry in series production, as a result of which the objective of minimizing the variants of the components employed and the complexity in handling fails to be attained optimally.
Although only one circuit substrate is involved when using circuit substrates having two different layouts for the circuitry applied to both sides (e.g. as in the case of a double-sided circuit board provided with tracks on both sides or a double-sided flexible circuit film printed on both sides) this still needs to be provided with tracks on both sides which, depending on the method employed in each case, may considerably add to the complexity in production and thus the costs involved.
It is thus the objective of the present invention to propose a circuit substrate assembly comprising a left-hand and a right-hand circuit substrate including electrical and/or electronic and/or electromechanical components positioned mirror-symmetrical to each other in which the number of component variants needing to be made available for series production including the number of variants of the circuitry for the left-hand and right-hand circuit substrate is a minimum.
This objective is achieved by the means as provided for in claim 1. The dependent claims relate to advantageous embodiments of the present invention.
In addition to the series production of circuit substrates for electromechanical car door locks, the same problem situation exists in the requirement for circuit substrates symmetrical in three-dimensional geometry as regards component positioning but asymmetrical as regards the circuit functionality of these symmetrically positioned components likewise e.g. in the series production of circuit substrates for left-hand and right-hand car seat adjustment, in the series production of vehicles having left-hand or right-hand drive or quite generally in any situation where a left-hand variant and a right-hand variant mirror-symmetrical thereto as regards the three-dimensional geometry of a circuit substrate needs to be produced in making use of but a single type of electrical and/or electronic components.